California sea cucumber

California sea cucumber 
The coast of British Columbia offers some of the best diving in the world.  The oceans abound with life of all kinds, much of it visible at low tide or in tide pools.  The California sea cucumber is a good example, I have seen them during low tides in shallow water while kayaking.  This particular specimen was photographed in an open tank with a water depth of only a few inches.  The tank itself was designed so people could get a good look at whatever marine life happened to be present.

Sea cucumbers belong to the same group of animals that include starfish, sand dollars, and sea urchins do.  This phylum is the echinoderms, and it contains some of the most bizarre and interesting organisms you could expect to find.   One of their wonderful features is the ability to regenerate lost body parts.  In the sea cucumber this is often related to it being attacked.  The animal will eviscerate its internal organs, which will crawl off in a safe direction, while the outside tissues are left to the whims of its aggressor. 

For a moment, imagine if our bodies behaved in such a manner.  Going to work one day you find yourself in a horrible accident and are left with multiple broken bones and blood leaking from multiple wounds.  Recognizing that the end is near, your internal organs gather together and exit the body through the largest orifice it can find.  While your body succumbs to the destruction around it, the rest of you makes it out to a safe place.  Later on, you arrive home, just as a bunch of internal organs which will start to regrow the outside tissues.  You say to your significant other, "You wouldn't believe the day I had.  Say, what's for dinner?"


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